This section is intended to provide a background or context to the invention that is recited in the claims The description herein may include concepts that could be pursued, but are not necessarily ones that have been previously conceived, implemented or described. Therefore, unless otherwise indicated herein, what is described in this section is not prior art to the description and claims in this application and is not admitted to be prior art by inclusion in this section.
The following abbreviations that may be found in the specification and/or the drawing figures are defined as follows:    3GPP third generation partnership project    BW bandwidth    CC component carrier    DL downlink (eNB to UE)    DRX discontinuous reception    eNB evolved Node B    E-UTRA evolved universal terrestrial radio access    HSPA-DC high speed packet access dual carrier    LTE long term evolution    LTE-A LTE advanced    PDCCH physical downlink control channel    RAN radio access network    RRC radio resource control    Rel release    TS technical specification    UE user equipment    UL uplink (UE to eNB)
The specification of a communication system known as evolved UTRAN (EUTRAN, also referred to as UTRAN-LTE or as E-UTRA) is currently nearing completion within the 3GPP. One specification of interest is 3GPP TS 36.300, V8.8.0 (2009-04), 3rd Generation Partnership Project; Technical Specification Group Radio Access Network; Evolved Universal Terrestrial Radio Access (EUTRA) and Evolved Universal Terrestrial Access Network (EUTRAN); Overall description; Stage 2 (Release 8), incorporated by reference herein in its entirety.
FIG. 1 reproduces FIG. 4.1 of 3GPP TS 36.300, and shows the overall architecture of the EUTRAN system (Rel-8). The EUTRAN system includes eNBs, providing the E-UTRA user plane and control plane (radio resource control) protocol terminations towards the UE. The eNBs are interconnected with each other by means of an X2 interface. The eNBs are also connected by means of an S1 interface to an evolved packet core (EPC), more specifically to a mobile management entity (MME) by means of a S1 MME interface and to a serving gateway (SGW) by means of a S1 interface. The S1 interface supports a many to many relationship between MMEs/Serving Gateways and eNBs.
The eNB hosts the following functions:    functions for Radio Resource Management: Radio Bearer Control, Radio Admission Control, Connection Mobility Control, Dynamic allocation of resources to UEs in both uplink and downlink (scheduling);    IP header compression and encryption of the user data stream;    selection of a MME at UE attachment;    routing of User Plane data towards Serving Gateway;    scheduling and transmission of paging messages (originated from the MME);    scheduling and transmission of broadcast information (originated from the MME or O&M (operation and maintenance)); and    measurement and measurement reporting configurations to provide mobility and scheduling.
Of particular interest herein are the further releases of 3GPP LTE (e.g., LTE Rel-10) targeted towards future IMT-A systems, referred to herein for convenience simply as LTE-Advanced (LTE-A). Reference in this regard may be made to 3GPP TR 36.913, V8.0.1 (2009-03), 3rd Generation Partnership Project; Technical Specification Group Radio Access Network; Requirements for Further Advancements for E-UTRA (LTE-Advanced) (Release 8), incorporated by reference herein in its entirety.
E-UTRAN introduced a DRX technique for the RRC-Connected mode such that, depending on the network configured DRX parameters, it is possible to achieve UE power saving while in the connected mode. It is expected that the future development of LTE-A and HSPA-DC will introduce yet another dimension to the DRX concept by adding a frequency dimension to the conventional time dimension.